Sunday, May 18, 2014

TPA for acute ishcemic stroke: trends in usage

Methods and Results—We analyzed all AIS patients (n=1 9093 895) and those arriving less than or equal to 2 hours and treated with tPA less than or equal to 3 hours after onset (n=50 798) from 2003 to 2011 in the American Heart Association’s Get with the Guideline–Stroke (GWTG–Stroke). Categorical data were analyzed by Pearson χ2 and continuous data by Wilcoxon test. Intravenous tPA use less than or equal to 3 hours after onset increased from 4.0% to 7.0% in all AIS admissions and 42.6% to 77.0% in AIS patients arriving less than or equal to 2 hours and fully eligible for tPA (P less than 0.001). In univariate analysis, tPA use increased over time, especially in those aged greater than 85 years, nonwhite, and with milder strokes (National Institutes of Health Stroke Scale 0–4). Door-to-image time (median 24 versus 20 minutes) and door-to-tPA time (median 81 versus 72 minutes) also improved, with ≈65% of tPA-treated patients getting brain imaging less than or equal to 25 minutes after arrival. Multivariable analysis showed that with each additional calendar year, the odds that an eligible patient would receive tPA increased by 1.37-fold, adjusting for other covariates.

Slow uptake. In 2003, eight years post NINDS, only 42.6% of eligible patients were treated. By 2011, sixteen years post NINDS, it's up to 77%. If you present to an ER eligible for TPA, with each passing year your odds of getting treated increase 37%.

Thrombolysis for ischemic stroke has an interesting history. Its slow uptake in clinical practice is due in part to a massive and highly organized push-back from the discipline of emergency medicine. Maybe that's not entirely a bad thing. Contrast it with those treatments that were rushed to widespread implementation after a single clinical trial only to suffer a reversal.